DynDNS and IPv6

as i have been struggeling for a bit to get IPv6 Working, i am writing down, what i have experienced so far.. this guid may not be complete, so expect things not to work.

Also IPv6 is qiute old (released in 1998), it is still not very common as its setup is a bit different.

IPv4 works with NAT, which means, that the Firewall/Modem of your SOHO- Server is the central point, which can be reached from the Internet. That Device can then be configured to accept connections on port- numbers an redirect them to hosts on the local net.

IPv6 has no NAT. Instead them Modem gets an adress Range, called the prefix - which ist the first half of your adress (the four Numbers in front of the first four colons) and in that range the Modem can assign Adresses to the devices in the Internet via DHCP which is mostly configured to work out of the Box (or they will choose their own IPv6, but this is not common).

So basically every Host in the local Network can be reached from the Internet. Its the Modems Firewall, which will prevent exposing all Hosts of the local net directly to the internet. Thus, the only thing you have to do, is to open Ports on some Device, which the Firewall will allow to pass from the internet to the local network.

DDClient can be used in the local server/host to assign some DNS- Record to an IP. It turned out, that the DDclient V3.8.3 of OpenSuSE Leap 15.5 was not able to work with IPv6 in the Version coming from the main Repositories.

Add the Repository https://download.opensuse.org/repositories/network/${releasever}/ with yast and update to the Packages of that Repository first, so you get ddclient V3.11.3, which is able to deal with ipv6.

The config is in /etc/ddclient.conf and it could contain e.g. those lines:

#01.01.2023 dnydns test
ssl=yes,
usev6=ifv6,
if=wlan0,
protocol=dyndns2,
server=dynv6.com,
login=none, password='blabla'
domainname.dynv6.net,cname.domainname.dynv6.net